internal/dinosql: Ignore sql-migrate rollbacks (#160)

Author: kyleconroy

README.md

@@ -249,7 +249,7 @@ Your favorite PostgreSQL / Go features are supported:
   - [ALTER TABLE](./examples/alter_table.md)
 - Go
   - [JSON struct tags](./examples/json_tags.md)
-  - [Goose migrations](./examples/goose.md)
+  - [Migration tools](./examples/migrations.md)
 
 A full, end-to-end example can be found in the sample
 [`ondeck`](./internal/dinosql/testdata/ondeck) package.

examples/goose.md

@@ -0,0 +1,52 @@
+# Migrations
+
+sqlc will ignore rollback statements when parsing migration SQL files. The following tools are current supported:
+
+- [goose](https://github.com/pressly/goose)
+- [sql-migrate](https://github.com/rubenv/sql-migrate)
+
+## goose
+
+```sql
+-- +goose Up
+CREATE TABLE post (
+    id    int NOT NULL,
+    title text,
+    body  text,
+    PRIMARY KEY(id)
+);
+
+-- +goose Down
+DROP TABLE post;
+```
+
+```go
+package db
+
+type Post struct {
+	ID    int
+	Title sql.NullString
+	Body  sql.NullString
+}
+```
+
+### sql-migrate
+
+```sql
+-- +migrate Up
+-- SQL in section 'Up' is executed when this migration is applied
+CREATE TABLE people (id int);
+
+
+-- +migrate Down
+-- SQL section 'Down' is executed when this migration is rolled back
+DROP TABLE people;
+```
+
+```go
+package db
+
+type People struct {
+	ID    int32
+}
+```

examples/migrations.md

@@ -0,0 +1,25 @@
+package dinosql
+
+import (
+	"bufio"
+	"strings"
+)
+
+// Remove all lines after a rollback comment.
+//
+// goose:       -- +goose Down
+// sql-migrate: -- +migrate Down
+func RemoveRollbackStatements(contents string) string {
+	s := bufio.NewScanner(strings.NewReader(contents))
+	var lines []string
+	for s.Scan() {
+		if strings.HasPrefix(s.Text(), "-- +goose Down") {
+			break
+		}
+		if strings.HasPrefix(s.Text(), "-- +migrate Down") {
+			break
+		}
+		lines = append(lines, s.Text())
+	}
+	return strings.Join(lines, "\n")
+}

internal/dinosql/goose.go

@@ -0,0 +1,45 @@
+package dinosql
+
+import (
+	"testing"
+
+	"github.com/google/go-cmp/cmp"
+)
+
+const inputGoose = `
+-- +goose Up
+ALTER TABLE archived_jobs ADD COLUMN expires_at TIMESTAMP WITH TIME ZONE;
+
+-- +goose Down
+ALTER TABLE archived_jobs DROP COLUMN expires_at;
+`
+
+const outputGoose = `
+-- +goose Up
+ALTER TABLE archived_jobs ADD COLUMN expires_at TIMESTAMP WITH TIME ZONE;
+`
+
+const inputMigrate = `
+-- +migrate Up
+-- SQL in section 'Up' is executed when this migration is applied
+CREATE TABLE people (id int);
+
+-- +migrate Down
+-- SQL section 'Down' is executed when this migration is rolled back
+DROP TABLE people;
+`
+
+const outputMigrate = `
+-- +migrate Up
+-- SQL in section 'Up' is executed when this migration is applied
+CREATE TABLE people (id int);
+`
+
+func TestRemoveRollback(t *testing.T) {
+	if diff := cmp.Diff(outputGoose, RemoveRollbackStatements(inputGoose)); diff != "" {
+		t.Errorf("goose migration mismatch:\n%s", diff)
+	}
+	if diff := cmp.Diff(outputMigrate, RemoveRollbackStatements(inputMigrate)); diff != "" {
+		t.Errorf("sql-migrate migration mismatch:\n%s", diff)
+	}
+}

internal/dinosql/goose_test.go

@@ -91,7 +91,7 @@ func ParseCatalog(schema string) (core.Catalog, error) {
 			merr.Add(filename, "", 0, err)
 			continue
 		}
-		contents := RemoveGooseRollback(string(blob))
+		contents := RemoveRollbackStatements(string(blob))
 		tree, err := pg.Parse(contents)
 		if err != nil {
 			merr.Add(filename, contents, 0, err)